[FEATURE] Add @Externalizable

[lsong98sh]

As it‘s name, simply generate writeExternal and readExternal for POJO.

[rspilker]

Without a before image (the code without lombok) and after image (the code you would write if lombok would support this) we cannot do anything.

[rspilker]

Also, please specify what would be the use case, other libraries that would consume these methods et cetera.

[mxmlnglt]

The purpose of this feature is probably the auto-generation of code to implement interface java.io.Externalizable: https://docs.oracle.com/javase/8/docs/api/java/io/Externalizable.html

Example code by Baeldung: https://www.baeldung.com/java-externalizable

[lsong98sh]

Sorry I'm a chinese. so I can only provide Chinese WebSite to explain Externalizable interface.
Thanks to mxmlnglt, the answer is exact what I want.

Recently, I'm working on a project that does a fast serialization job of an Java Object.
A project that almost the same as Kyro 【 https://github.com/EsotericSoftware/kryo】
But uses CgLib to generate byecode。

First, I wrote my own UnsafeBufferedOutput, and manually implememts the Externalizable interface.
The test result is about 25% faster that Kyro.
So the rest of the work can ben done in two ways. Using CgLib to generate a Proxy（somthing like BeanCopier ) or using ask Lombok to generate the source。

[rspilker]

We're not going to add this. Using java serialization is basically broken, so we're not going to create code to make it easier.